A young group from the Boston area -- in fact, none of the members looked to be older than 15 -- Flat Earth Society recorded a rare album in 1968 that became a prime collectible two or three decades later. This was probably based more on its rarity than the actual music, as the record was marketed by Waleeco candy bars -- you could mail-order the album with half a dozen candy wrappers and $1.50. Those consumers that took advantage of the offer were rewarded with competent, but somewhat generic, psychedelic rock, with the prominent electric keyboards that were characteristic of much of the Boston sound.